Subpixel arrangements of displays and method for rendering the same

ABSTRACT

An apparatus including a display and control logic. In one example, the display includes an array of subpixel groups. Each of the subpixel groups includes one subpixel in a first color, two subpixels in a second color, and two subpixels in a third color. Subpixel groups in each row of the array are repeated. Subpixel groups in each row of the array are staggered relative to subpixels groups in an adjacent row of the array. The control logic is operatively coupled to the display and configured to receive display data and convert the display data into control signals for driving the array of subpixel groups.

BACKGROUND

The disclosure relates generally to displays, and more particularly, tosubpixel arrangements of displays and a method for rendering the same.

Displays are commonly characterized by display resolution. With is theabsolute number of distinct pixels in each dimension that can bedisplayed (e.g., 1920×1080) or by display density (a.k.a. pixels perinch—PPI) concerning the relative numbers of pixels per inch. Manydisplays are for various reasons, not capable of displaying differentcolor channels at the same site. Therefore, the pixel grid is dividedinto single-color parts that contribute to the displayed color whenviewed from a distance. In some displays, such as liquid crystal display(LCD), organic light-emitting diode (OLED) display, electrophoretic ink(E-ink) display, electroluminescent display (ELD) or light-emittingdiode (LED) lamp display, these single-color parts are separatelyaddressable elements, which are known as subpixels.

Various subpixel arrangements (layouts, schemes) have been proposed tooperate with a proprietary set of subpixel rendering algorithms in orderto improve the display quality by increasing the display density of adisplay and by anti-aliasing text with greater details. For example,LCDs typically divide each pixel into three strip subpixels (e.g., red,green, and blue subpixels) or four quadrate subpixels (e.g., red, green,blue, and white subpixels) so that each pixel can present brightness anda full color. Compared with LCDs, it is even more difficult to increasethe display density of OLED displays by reducing the size of individualsubpixel because the organic light-emitting layers of OLEDs arefabricated by evaporation techniques using fine metal masks (FMMs). Dueto the process accuracy for patterning organic materials using FMMs, theminimum size of each organic light-emitting layer is limited. Toovercome such limitation, various subpixel arrangements with subpixelrendering algorithms have been applied to increase the display densityof OLED displays.

In an OLED display having a “diamond” pixel array 2600 shown in FIG. 26,the green subpixels G are repeated M a single line, while red subpixelsR and blue subpixels B are larger and alternate between the lines ofgreen subpixels. The subpixel array 2600 is divided into various pixels,each of which consists of one red subpixel and two half-green subpixels(pixel 2602) or consists of one blue subpixel and two half-greensubpixels (pixel 2604). Apparently, in this example, only the number ofgreen subpixels is the same as the number of pixels on the display,while the number of either the red or blue subpixels is only half of thenumber of pixels in display. That is, the actual color resolution of redor blue subpixels is only half of the display resolution.

Accordingly, there exists a need for improved subpixel arrangements ofdisplays and a method for rendering the same to overcome theabove-mentioned problems.

SUMMARY

The present disclosure relates generally to displays, and moreparticularly, to subpixel arrangements of displays and a method forrendering the same.

In one example, an apparatus including a display and control logic isprovided. The display includes an array of subpixel groups. Each of thesubpixel groups includes one subpixel in a first color, two subpixels ina second color, and two subpixels in a third color. Subpixel groups ineach row of the array are repeated. Subpixel groups in each row of thearray are staggered relative to subpixels groups in an adjacent row ofthe array. The control logic is operatively coupled to the display andconfigured to receive display data and convert the display data intocontrol signals for driving the array of subpixel groups.

In another example, an apparatus including a display and control logicis provided. The display includes a display panel having alight-emitting substrate and a driving substrate. The light-emittingsubstrate includes an array of subpixel groups. A subpixel of each ofthe subpixel groups corresponds to an OLED. The driving substrateincludes an array of driving elements, each driving element configuredto drive a respective OLED. Each of the subpixel groups includes oneOLED in a first color, two OLEDs in a second color, and two OLEDs in athird color. Subpixel groups in each row of the array are repeated.Subpixel groups in each row of the array are staggered relative tosubpixels groups in an adjacent row of the array. The control logic isoperatively coupled to the display and configured to receive displaydata and convert the display data into control signals for driving thearray of subpixel groups.

In still another example, an apparatus including a display and controllogic is provided. The display includes an array of LED lamps. Each ofthe LED lamps includes one LED in a first color, two LED in a secondcolor, and two LEDs in a third color. LED lamps in each row of the arrayare repeated. LED lamps in each row of the array are staggered relativeto LED lamps in an adjacent row of the array. The control logic isoperatively coupled to the display and configured to receive displaydata and convert the display data into control signals for driving thearray of LED lamps.

In yet another example, an apparatus including a display and controllogic is provided. The display includes an array of subpixel groups.Each of the subpixel groups includes two subpixels in a first color, twosubpixels in a second color, and two subpixels in a third color.Subpixel groups in each row of the array are repeated. Subpixel groupsin each row of the array are staggered relative to subpixels groups inan adjacent row of the array. The control logic is operatively coupledto the display and configured to receive display data and convert thedisplay data into control signals for driving the array of subpixelgroups.

In a different example, a method for subpixel rendering on a display isprovided. The display includes an array of subpixel groups. Each of thesubpixel groups includes. One subpixel in a first color, two subpixelsin a second color, and two subpixels in a third color. Subpixel groupsin each row of the array are repeated. Subpixel groups in each row ofthe array are staggered relative to subpixels groups in an adjacent rowof the array. Each of the subpixel groups is divided into two pixelssuch that each of the two pixels includes one of the two subpixels inthe second color and one of the two subpixels in the third color, andthat the subpixel in the first color is shared by the two pixels. Aplurality pieces of display data for displaying a plurality of pixelsare first received. Each piece of display data includes a first, asecond, and a third components representing the first, second, and thirdcolors, respectively. Control signals for rendering the array ofsubpixel groups on the display are then provided based on the pluralitypieces of display data.

Other concepts relate to software for implementing the method forsubpixel rendering on a display. A software product, in accord with thisconcept, includes at least one machine-readable non-transitory mediumand information carried by the medium. The information carried by themedium may be executable program code data regarding parameters inassociation with a request or operational parameters, such asinformation related to a user, a request, or a social group, etc.

In one example, a non-transitory machine-readable medium havinginformation recorded thereon for subpixel rendering on a display, wherewhen the information is read by the machine, causes the machine toperform a series of steps. The display includes an array of subpixelgroups. Each of the subpixel groups includes one subpixel in a firstcolor, two subpixels in a second color, and two subpixels in a thirdcolor. Subpixel groups in each row of the array are repeated. Subpixelgroups in each row of the array are staggered relative to subpixelsgroups in an adjacent row of the array. Each of the subpixel groups isdivided into two pixels such that each of the two pixels includes one ofthe two subpixels in the second color and one of the two subpixels inthe third color, and that the subpixel in the first color is shared bythe two pixels. A plurality pieces of display data for displaying aplurality of pixels are first received. Each piece of display dataincludes a first, a second, and a third components representing thefirst, second, and third colors, respectively. Control signals forrendering the array of subpixel groups on the display are then providedbased on the plurality pieces of display data.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments will be more readily understood in view of the followingdescription when accompanied by the below figures and wherein likereference numerals represent like elements, wherein:

FIG. 1 is a block, diagram illustrating an apparatus including a displayand control logic in accordance with one embodiment set forth in thedisclosure;

FIG. 2 is a side-view diagram illustrating one example of the displayshown in FIG. 1 in accordance with one embodiment set forth in thedisclosure;

FIG. 3 is a depiction of a subpixel arrangement of a display inaccordance with one embodiment set forth in the disclosure;

FIG. 4 is a depiction of a red, green, and blue subpixel arrangement ofan OLED display in accordance with one embodiment set forth in thedisclosure;

FIG. 5 is a side-view diagram illustrating an organic light-emittinglayer shared by two subpixel in accordance with one embodiment set forthin the disclosure;

FIG. 6 is a depiction of masks used for fabricating organiclight-emitting layers of the red, green, and blue OLEDs shown in FIG. 4in accordance with one embodiment set forth in the disclosure;

FIG. 7 is a schematic diagram of pixel division for the subpixelarrangement shown in FIG. 4 in accordance with one embodiment set forthin the disclosure;

FIG. 8 is a schematic diagram of one example of wire layout for thesubpixel arrangement shown in FIG. 4 in accordance with one embodimentset forth in the disclosure;

FIG. 9 is a schematic diagram of another example of wire layout for thesubpixel arrangement shown in FIG. 4 in accordance with one embodimentset forth in the disclosure;

FIG. 10 is a schematic diagram of still another example of wire layoutfor the subpixel arrangement shown in FIG. 4 in accordance with oneembodiment set forth in the disclosure;

FIG. 11 is a depiction of displaying a white screen on a display usingthe subpixel arrangement shown in FIG. 4 in accordance with oneembodiment set forth in the disclosure;

FIG. 12 is a depiction of displaying, a single green vertical line on adisplay using the subpixel arrangement shown in FIG. 4 in accordancewith one embodiment set forth in the disclosure;

FIG. 13 is a depiction of displaying two adjacent green vertical lineson a display using the subpixel arrangement shown in FIG. 4 inaccordance with one embodiment set forth in the disclosure;

FIG. 14 is a depiction of displaying two separate green vertical lineson a display using the subpixel arrangement shown in FIG. 4 inaccordance with one embodiment set forth in the disclosure;

FIG. 15 is a depiction of displaying a single blue vertical line on adisplay using the subpixel arrangement shown in FIG. 4 in accordancewith one embodiment set forth in the disclosure;

FIG. 16 is a depiction of displaying two adjacent blue vertical lines ona display using the subpixel arrangement shown in FIG. 4 in accordancewith one embodiment set forth in the disclosure;

FIG. 17 is a depiction of displaying two separate blue vertical lines ona display using the subpixel arrangement shown in FIG. 4 in accordancewith one embodiment set forth in the disclosure;

FIG. 18 is a depiction of a subpixel arrangement of an LED lamp displayin accordance with one embodiment set forth in the disclosure;

FIG. 19 is a schematic diagram of pixel division for the subpixelarrangement shown in FIG. 18 in accordance with one embodiment set forthin the disclosure;

FIG. 20 is a flow chart illustrating a method for rendering subpixels ofthe display shown in FIG. 1 in accordance with one embodiment set forthin the disclosure;

FIG. 21 is a schematic diagram illustrating an algorithm forimplementing the method shown in FIG. 20 in accordance with oneembodiment set forth in the disclosure;

FIG. 22 is a depiction of another subpixel arrangement of an OLEDdisplay in accordance with one embodiment set forth in the disclosure;

FIG. 23 is a depiction of still another subpixel arrangement of an OLEDdisplay in accordance with one embodiment set forth in the disclosure;

FIG. 24 is a diagram illustrating one example of implementing thecontrol logic shown in FIG. 1 as an integrated circuit (IC) chip inaccordance with one embodiment set forth in the disclosure;

FIG. 25 is a diagram illustrating another example of implementing thecontrol logic shown in FIG. 1 as an IC chip in accordance with oneembodiment set forth in the disclosure; and

FIG. 26 is a depiction of a prior art red, green, and blue subpixelarrangement of an OLED display.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are setforth by way of examples in order to provide a thorough understanding ofthe relevant disclosures. However, it should be apparent to thoseskilled in the art that the present disclosure may be practiced withoutsuch details, in other instances, well known methods, procedures,systems, components, and/or circuitry have been described at arelatively high-level, without detail, in order to avoid unnecessarilyobscuring aspects of the present disclosure.

Among other novel features, the present disclosure provides the abilityto further increase the actual color resolution by overcoming thelimitations of mask-based organic materials evaporation techniques. Thenovel subpixel arrangements of the present disclosure are fullycompatible with existing fabrication techniques and thus, ensure therelative high yield and low production cost. The novel subpixelarrangements of the present disclosure also make the color distributionof the display more uniform compared with known solutions, therebyincreasing the user experience. The novel subpixel arrangements of thepresent disclosure can be applied to various displays, such as but notlimited to, top-emitting IDLED displays, bottom-emitting OLED displays,or billboard displays with lamps.

Additional novel features will be set forth in part in the descriptionwhich follows, and in part will become apparent to those skilled in theart upon examination of the following and the accompanying drawings ormay be learned by production or operation of the examples. The novelfeatures of the present disclosure may be realized and attained bypractice or use of various aspects of the methodologies,instrumentalities, and combinations set forth in the detailed examplesdiscussed below.

FIG. 1 illustrates an apparatus 100 including a display 102 and controllogic 104. The apparatus 100 may be any suitable device, for example, atelevision set, laptop computer, desktop computer, netbook computer,media center, handheld device (e.g., dumb or smart phone, tablet, etc.),electronic billboard, electronic sign, gaming console, set-top box,printer, or any other suitable device. In this example, the display 102is operatively coupled to the control logic 104 and is part of theapparatus 100, such as but not limited to, a television screen, computermonitor, dashboard, head-mounted display, electronic billboard, orelectronic sign. The display 102 may be an LCD, OLED display, E-inkdisplay, ELD, billboard display with LED or incandescent lamps, or anyother suitable type of display. The control logic 104 may be anysuitable hardware, software, firmware, or combination thereof,configured to receive display data 106 and render the received displaydata 106 into control signals 108 for driving the subpixels on thedisplay 102. For example, subpixel rendering algorithms for varioussubpixel arrangements may be part of the control logic 104 orimplemented by the control logic 104. The control logic 104 may includeany other suitable components, including an encoder, a decoder, one ormore processors, controllers (e.g., timing, controller), and storagedevices. The control logic 104 may be implemented as a standaloneintegrated circuit (IC) chip or part of the driving circuits of thedisplay 102. One example of the control logic 104 and a method forrendering subpixels of the display 102 implemented by the control logic104 are described below in detail. The apparatus 100 may also includeany other suitable component such as, but not limited to, a speaker 110and an input, device 112, e.g., a mouse, keyboard, remote controller,handwriting device, camera, microphone, scanner, etc.

In one example, the apparatus 100 may be a laptop or desktop computerhaving a display 102. In this example, the apparatus 100 also includes aprocessor 114 and memory 116. The processor 114 may be, for example, agraphic processor (e.g., GPU), a general processor (e.g., APU,accelerated processing unit, GPGPU, general-purpose computing on GPU),or any other suitable processor. The memory 116 may be, for example, adiscrete frame buffer or a unified memory. The processor 114 isconfigured to generate display data 106 in display frames and temporallystore the display data 106 in the memory 116 before sending it to thecontrol logic 104. The processor 114 may also generate other data, suchas but not limited to, control instructions 118 or test signals, andprovide them to the control logic 104 directly or through the memory116. The control logic 104 then receives the display data 106 from thememory 116 or from the processor 114 directly.

In another example, the apparatus 100 may be a television set having adisplay 102. In this example, the apparatus 100 also includes a receiver120, such as but not limited to, an antenna, radio frequency receiver,digital signal tuner, digital display connectors, e.g., DVI,DisplayPort, USB, Bluetooth, WiFi receiver, or Ethernet port. Thereceiver 120 is configured to receive the display data 106 as an inputof the apparatus 100 and provide the native or modulated display data106 to the control logic 104.

In still another example, the apparatus 100 may be a handheld device,such as a smart phone or a tablet, in this example, the apparatus 100includes the processor 114, memory 116, and the receiver 120. Theapparatus 100 may both generate display data 106 by its processor 114and receive display data 106 through its receiver 120. For example, theapparatus 100 may be a handheld device that works as both a mobiletelevision and a mobile computing device. In any event, the apparatus100 at least includes the display 102 with specifically designedsubpixel arrangements as described below in detail and the control logic104 for the specifically designed subpixel arrangements of the display102.

Referring now to FIGS. 24 and 25, the control logic 104 is implementedas a standalone IC chip in these examples, such as a field-programmablegate array (FPGA) or an application-specific integrated circuit (ASIC).In one example illustrated in FIG. 24, the apparatus 100 is a handhelddevice such as a smartphone or a tablet, which includes the display 102with driving circuits 2402 and a motherboard 2404. The display 102 isconnected to the motherboard 2404 through a flexible printed circuit(FPC) 2406. The IC chip implementing the control logic 104 is arrangedon the FPC 2406 such that the handheld device can be easily integratedwith the control logic 104 without changing the motherboard 2404. Inanother example illustrated in FIG. 25, the IC chip implementing thecontrol logic 104 is arranged on the motherboard 2404 to reduce the costof the handheld device.

FIG. 2 illustrates one example of a display 102 including a group ofsubpixels 202, 204, 206, 208, 210. The display 102 may be any suitabletype of display, for example, OLED displays, such as an active-matrix(AM) OLED display, passive-matrix (PM) OLED display, or any othersuitable display. The display 102 may include a display panel 212operatively coupled to the control logic 104.

In this example, the display panel 212 includes a light-emittingsubstrate 214 and a driving substrate 216. As shown in FIG. 2, thelight-emitting substrate 214 includes a plurality of OLEDs 218, 220,222, 224, 226 corresponding to the plurality of subpixels 202, 204, 206,208, 210, respectively. A, B, and C in FIG. 2 denote OLEDs in threedifferent colors, such as but not limited to, red, green, blue, yellow,cyan, magenta, or white. The light-emitting substrate 214 also includesa black matrix 228 disposed between the OLEDs 218, 220, 222, 224, 226,as shown in FIG. 2. The black matrix 228, as the borders of thesubpixels 202, 204, 206, 208, 210, is used for blocking lights comingout from the parts outside the OLEDs 218, 220, 222, 224, 226. Each OLED218, 220, 222, 224, 226 in the light-emitting substrate 214 can emitlight in a predetermined color and brightness. In this example, thedriving substrate 216 includes a plurality of driving elements 230, 232,234, 236, 238, such as thin film transistors (TFTs), corresponding tothe plurality of OLEDs 218, 220, 222, 224, 226 of the plurality ofsubpixels 202, 204, 206, 208, 210, respectively. The driving elements230, 232, 234, 236, 238 may be individually addressed by the controlsignals 108 from the control logic 104 and are configured to drive thecorresponding subpixels 202, 204, 206, 208, 210, by controlling thelight emitting from the respective OLEDs 218, 220, 222, 224, 226according to the control signals 108. The display panel 212 may includeany other suitable component, such as one or more glass substrates,polarization layers, or a touch panel, as known in the art.

As shown in FIG. 2, each of the plurality of subpixels 202, 204, 206,208, 210 is constituted by at least an OLED and a corresponding drivingelement. Each OLED may be formed by a sandwich structure of an anode, anorganic light-emitting layer, and a cathode, as known in the art.Depending on the characteristics (e.g., material, structure, etc.) ofthe organic light-emitting layer of the respective OLED, a subpixel maypresent a distinct color and brightness. In this example, subpixels 202,204, 206, 208, 210, as a subpixel group, are divided into two pixels.The first pixel 240 includes subpixel B 204 and subpixel C 206, thesecond pixel 242 includes subpixel B 208 and subpixel C 210, andsubpixel A 202 is shared by both the first and second pixels 240, 242.Here, since the display data 106 is usually programmed at the pixellevel, the subpixels of each pixel or the multiple subpixels of adjacentpixels may be addressed collectively by subpixel rendering to presentthe appropriate brightness and color of each pixel, as designated in thedisplay data 106, with the help of subpixel rendering algorithms.However, it is understood that, in other examples, the display data 106may be programmed at the subpixel level such that the display data 106can directly address individual subpixel without the need of subpixelrendering. Because it usually requires three primary colors—RGB topresent a full color, specifically designed subpixel arrangements areprovided below in detail for the display 102 to achieve an appropriateactual color resolution.

Although FIG. 2 is illustrated as an OLED display, it is understood thatit is provided for an exemplary purpose only and without limitations. Asnoted above, in addition to an OLED display, the display 102 may be anLCD, E-ink display, ELD, billboard display with LED or incandescentlamps, or any other suitable type of display.

FIG. 3 depicts a subpixel arrangement of a display in accordance withone embodiment set forth in the disclosure. FIG. 3 may be, for example,a plan view of the display 102 and depicts one example of subpixelarrangements of the display 102. The display 102 includes an array 300of subpixel groups 302. Each subpixel group 302 in this embodimentincludes five subpixels: one subpixel in a first color A, two subpixelsin a second color B, and two subpixels in a third color C. A, B, and Cin FIG. 3 denote three different colors, such as but not limited to,red, green, blue, yellow, cyan, magenta, or white. Subpixel groups 302in each row (e.g., Row 1, Row 2, Row 3, Row 4, etc.) of the array 300are repeated along the horizontal direction. Subpixel groups 302 in eachrow of the array 300 are staggered relative to subpixels groups 302 inan adjacent row of the array 300. In other words, subpixel groups 302 inadjacent rows are staggered along the horizontal direction. For example,as shown in FIG. 3, subpixel groups 302 in Row 1 are staggered relativeto subpixel groups 302 in Row 2 by a distance of D. It is understoodthat the distance D is less than the width W of the subpixel group 302.In one example, the distance D equals ½ of the width W of the subpixelgroup 302. In this embodiment, subpixel groups 302 in interval rows arealigned along the vertical direction. That is, subpixel groups 302 ineach odd row (e.g., Row 1, Row 3, etc.) are aligned along the verticaldirection, and subpixel groups 302 in each even row (e.g., Row 2, Row 4,etc.) are aligned along the vertical direction. Stated in another way,subpixel groups 302 in each row are arranged repeatedly, and thesubpixel groups 302 in adjacent rows are arranged shifted from eachother by, for example, ½ of the repeat pitch.

In this embodiment, the five subpixels A, B, B, C, and C are arranged inthe same pattern in each subpixel group 302. For each subpixel group302, the two subpixels in the second color B are on different sides ofthe subpixel in the first color A along the horizontal direction, andthe two subpixels in the third color C are on different sides of thesubpixel in the first color A along the horizontal direction as well.That is, in the horizontal direction, subpixel A is between the twosubpixels B and also between the two subpixels C. In other words, ineach subpixel group 302, one subpixel B and one subpixel C are in theleft part of the subpixel group 302, the other subpixel B and the othersubpixel C are in the right part of the subpixel group 302, and thesubpixel A is in the middle of the subpixel group 302.

In this embodiment, in each subpixel group 302, one subpixel B isaligned with one subpixel C along, the vertical direction on the leftside of the subpixel A, and the other subpixel B is aligned with theother subpixel C along the vertical direction on the right side of thesubpixel A. The two subpixels B are abutted along the horizontaldirection, and the two subpixels C are aligned along the horizontaldirection as well. In other words, the two subpixels in the same colors(i.e., B and B, or C and C) are arranged flush with each otherhorizontally, and the two subpixels in the different colors (i.e., B andC) are arranged flush with each other vertically. It is understood thateven if two subpixels have different sizes and/or shapes, they areconsidered as being “aligned” if the centers of the two subpixels arealigned vertically or horizontally.

FIG. 4 depicts a red, green, and blue subpixel arrangement of an OLEDdisplay in accordance with one embodiment set forth in the disclosure.FIG. 4 may be, for example, a plan view of the display 102 and depictsone example of subpixel arrangements of the display 102. In thisembodiment, each subpixel corresponds to an OLED. The same subpixelarrangement illustrated with respect to FIG. 3 is applied to the array400 of subpixel groups 402 in this example. As shown in FIG. 4, eachsubpixel group 402 includes one blue OLED B, two green OLEDs G, and twored OLEDs R. In this embodiment, subpixel groups 402 are repeatedhorizontally in the same row and are staggered relative to subpixelgroups 402 in the adjacent row by half of the width of the subpixelgroup 402. In each subpixel group 402, one green OLEO and one red ° LEDare disposed on the left side of the blue OLED, and the other green OLEDand the other red OLED are disposed on the right side of the blue OLED.It is understood that although FIG. 4 shows that the green OLEDs areabove the red ° LEDs in each subpixel group 402, their positions may beexchanged in other examples. In other words, the red OLEDs may be abovethe blue OLEDs in each subpixel group 402.

In this embodiment, the size of the blue OLED is larger than the size ofany one of the two green OLEDs and the two red OLEDs. Stated in anotherway, the blue OLED is the largest subpixel among the five subpixels ineach subpixel group 402. In this embodiment, each subpixel has asubstantially rectangular shape with curved corners. However, it isunderstood that the shape of each subpixel in other examples may vary.Other shapes of the subpixels include, but are not limited to,substantially round, triangle, square, pentagon, hexagon, heptagon,octagon, or any other suitable shape. The regions between the subpixelsmay be filled with the black matrix as noted above. In this embodiment,the two been OLEDs in each subpixel group 402 have the same shape andsize, and the two red OLEDs have the same shape and size as well. Inother words, subpixels in the same color in each subpixel group 402 aregeometrically identical. In one example, each of the two green OLEDs andtwo red OLEDs has the same shape and size. That is, except for thelargest blue subpixel, each of the subpixels in the subpixel group 402is geometrically identical in one example. It is understood that, inother examples, each subpixel group may include one red OLED, two greenOLEDs, and two blue OLEDs, and the red OLED is in the middle of thesubpixel group and has the largest size among the five OLEDs in thesubpixel group.

In this embodiment, each of the two green OLEDs in a subpixel group 402shares the same organic light-emitting layer with a respective greenOLED in the adjacent subpixel group 402 in the same row of the array400. Similarly, each of the red OLEDs in one subpixel group 402 sharesthe same organic light-emitting, layer with a respective red OLED in theadjacent subpixel group 402 in the same row. The dashed lines in FIG. 4show the regions of organic light-emitting layers. For example, thegreen OLED 404 and the green OLED 406 in the two adjacent subpixelgroups 402 share the same organic light-emitting layer, so do the redOLEDs 408, 410. That is, a common organic light-emitting layer is usedby adjacent OLEDs in the same color. Referring now to FIG. 5, a firstOLED 502 and a second OLED 504 in the same color are adjacent to eachother and share the same organic light-emitting layer 506. Although thetwo adjacent OLEDs 502, 504 share the same organic light-emitting layer506, they are distinguishable by separate anodes and/or cathodes. Inthis example, the first OLED 502 has its own anode 508 and cathode 510for applying current through the organic light-emitting layer 506, andthe second OLED 504 has its own anode 512 and cathode 514 as well. It isunderstood that in other examples, the two OLEDs 502, 504 may also sharethe same anode or cathode.

As discussed above, the bottle neck of increasing the pixel density ofOLED displays is the minimum size of each organic light-emitting layerlimited by the pattern accuracy of masks used in organic materialsevaporation. In this embodiment, this limitation is further overcomebecause the blue OLED has a relative large size and the adjacentgreen/red pixels can share a common organic light-emitting layer with arelative large size. Referring now to FIG. 6, masks (e.g., FMMs) usedfor fabricating organic light-emitting layers of the red, green, andblue OLEDs shown in FIG. 4 are illustrated. The first mask 602 is usedfor fabricating, the organic light-emitting layers of the red or greenOLEDs by evaporation technique. Each opening 604 on the first mask 602corresponds to a common organic light-emitting layer shared by twoadjacent red or green OLEDs. The layout of the openings 604 correspondsto the arrangement of the green or red subpixels shown in FIG. 4. Thesecond mask 606 is used for fabricating the organic light-emittinglayers of the blue OLEDs. Each opening 608 on the second mask 606corresponds to the organic light-emitting layer of each blue OLED. Thelayout of the openings 608 corresponds to the arrangement of the bluesubpixels shown in FIG. 4. It is understood that in other examples, thefirst mask 602 may be used for fabricating the organic light-emittinglayers of the blue or green OLEDs, and the second mask 606 may be usedfor fabricating the organic light-emitting layers of the red OLEDs.

FIG. 7 illustrates one example of pixel division for the subpixelarrangement shown in FIG. 4. In this example, each subpixel group 402 isdivided into two pixels 702, 704 such that, each of the two pixels 702,704 includes one of the two subpixels in the second color (e.g., G) andone of the two subpixels in the third color R), and that the subpixel inthe first color (e.g., B) is shared by the two pixels 702, 704. As shownin FIG. 7, the subpixel group 402 is evenly divided through the middleof the blue OLED into a left part corresponding to one pixel 702, and aright part corresponding to another pixel 704. The pixel 702 includesone green OILED, one red OLED, and the left part of the blue OLED; thepixel 704 includes one green OLED, one red OLED, and the right part ofthe blue OLED. That is, each blue OLED on the display is shared by twoadjacent pixels. As each blue OLED has only one organic light-emittinglayer and one set of anode/cathode, it is necessary to implement aspecial subpixel rendering algorithm in the control logic 104 when theblue OLED is shared by two pixels. The details of the subpixel renderingalgorithm are described below with respect to FIGS. 20-21. In thisexample, the numbers of green and red subpixels are the same as thenumber of pixels on the display, and only the number of the bluesubpixels is half of the number of pixels on the display. Therefore,compared with the prior art example shown in FIG. 26, the actual colorresolution in this embodiment is increased. Moreover, each pixel 702,704 in this embodiment includes all three primary colors—RGB, which isalso superior over the prior art example shown in FIG. 26.

In this embodiment, due to the staggered arrangement between adjacentrows, the left and right edges of the display become irregular. In oneexample, a black resin layer with a serrated edge 706 is used to coverthe edges of the display such that the size and shape of the blue OLE-Ds708 along the edges do not change. In this example, the same subpixelrendering algorithm can be applied to all the blue OLEDs including those708 along the edges of the display. However, the serrated shape alongthe edges of the display is undesirable, in particular, when the size ofeach pixel is relative large. In another example, a black resin layerwith a flat edge 710 is used to cover the edges of the display such thateach blue OLED 712 along the edges is only half of a regular blue OLED.In this example, the subpixel rendering algorithm needs to be modifiedto render the blue OLEDs 712 along the edges of the display differently.For example, each blue OLED 712 along the edges is no longer shared bytwo pixels; rather it is included in only one pixel. Thus, the specialtreatment for the blue OLEDs may not be necessary for those 712 alongthe edges of the display. It is understood that, in other examples, thered OLED, rather than the blue OLED, may be the largest OLED and in themiddle of each subpixel group, which is shared by two adjacent pixels.

FIG. 8 depicts one example of wire layout for the subpixel arrangementshown in FIG. 4. In this example, the dashed lines illustrate theregions of organic light-emitting layers, and T is the switchingtransistor (e.g., a TFT) for each OLED. In this example, those datalines 802 passing through the blue or red OLEDs (the largest OLED in themiddle of each subpixel group) are used only for transmitting data ofblue or red subpixels. Thus, the signal duty ratio of the data lines inthis example is only 50%, with half of the frames are blank.Accordingly, the bandwidth of the display data cannot be reduced in thisexample. However, the wire layout in this example is particular suitablefor bottom-emitting, OLED displays as this layout can increase theaperture ratio of bottom-emitting OLED displays.

FIG. 9 depicts another example of wire layout for the subpixelarrangement shown in FIG. 4. In this example, the dashed linesillustrate the regions of organic light-emitting, layers, and T is theswitching transistor for each OLED. In this example, the number of datalines is reduced compared with the example in FIG. 8 such that thesignal duty ratio of each data line increases to 100%, thereby reducingthe bandwidth of the display data, reducing the width of IC, andreducing the number of source pins. However, as some switchingtransistors 902 of the blue or red OLEDs (the largest OLED in the middleof each subpixel group) cross adjacent data lines, anti-coupling, issuesneed to addressed in layout design.

FIG. 10 depicts still another example of wire layout for the subpixelarrangement shown in FIG. 4. In this example, the dashed linesillustrate the regions of organic light-emitting layers, and T is theswitching transistor for each OLED. As the OLEDs in different colorshave different sizes, the edges between organic light-emitting layersare not aligned in the vertical direction. Thus, in this example, somedata lines 1002 are polygonal lines that extend along the edges oforganic light-emitting layers. These polygonal data lines 1002 in thisexample are all single data lines. Other data lines 1004 passing throughthe blue or red OLEDs (the largest OLED in the middle of each subpixelgroup) are double straight lines as shown in FIG. 10. Similar to theexample in FIG. 9, the number of data lines is reduced compared with theexample in FIG. 8 such that the signal duty ratio of each data lineincreases to 100%, thereby reducing the bandwidth of the display data,reducing the width of IC, and reducing the number of source pins.

FIGS. 11-17 depict various examples of displaying different patterns ona display using the subpixel arrangement shown in FIG. 4. In FIG. 11,each subpixel is fully turned on (i.e., the value of each subpixel is255), and a white screen is displayed. In FIG. 12, a single greenvertical line 1202 is displayed by fully turning on half of the greensubpixels (i.e., the value of the green subpixel is 255) in thecorresponding subpixel groups 1204, 1206. For example, in each odd rowof subpixels, the green subpixels in the right part of the correspondingsubpixel groups 1204 are turned on; in each even row of subpixels, thegreen subpixels in the left part of the corresponding subpixel groups1206 are turned on. It is understood that because of the staggeredarrangement between adjacent rows, the green subpixels in adjacent rowsare not strictly aligned, in the vertical direction and thus, the singlegreen vertical line 1202 in this example is not a straight line.However, the human vision system would consider the single greenvertical line 1202 as a straight line when viewed from a distance.

In FIG. 13, two adjacent green vertical lines 1302, 1304 are displayedby fully turning on half or all of the green subpixels (i.e., the valueof the green subpixel is 255) in the corresponding subpixel groups 1306,1308, 1310. In each odd row of subpixels, half of the green subpixels inthe two adjacent subpixel groups 1306, 1308 are turned on. For example,the green subpixels in the right part of the corresponding subpixelgroups 1306 in each odd row are turned on, and the green subpixels inthe left side of the corresponding subpixel groups 1308 in each odd roware turned on. Subpixel groups 1306 and subpixel groups 1308 areadjacent to each other in each odd tow. In each even row, all the greensubpixels in the corresponding subpixel groups 1310 are turned on.Similarly, the human vision system would consider the two adjacent greenvertical lines 1302, 1304 as two straight lines when viewed from adistance.

In FIG. 14, two separate green vertical lines 1402, 1404 are displayedby fully turning on half of the green subpixels (i.e., the value of thegreen subpixel is 255) in the corresponding subpixel groups 1406, 1408,1410, 1412. In each odd row of subpixels, half of the green subpixels inthe two adjacent subpixel groups 1406, 1408 are turned on; in each evenrow of subpixels, half of the green subpixels in the two adjacentsubpixel groups 1410, 1412 are turned on. For example, the greensubpixels in the right part of the corresponding subpixel groups 1406,1408 in each odd row are turned on, and the green subpixels in the leftpart of the corresponding subpixel groups 1410, 1412 in each even roware turned on. Subpixel groups 1406 and subpixel groups 1408 areadjacent to each other in each odd row, and subpixel groups 1410 andsubpixel groups 1412 are adjacent to each other in each even row.Similarly, the human vision system would consider the two separate greenvertical lines 1402, 1404 as two straight lines when viewed from adistance. It is understood although only green vertical line(s) aredisplayed in the examples of FIGS. 12-14, red vertical line(s) can alsobe displayed in the same manner as shown in the examples of FIGS. 12-14by turning on half and/or all of the red subpixels in the correspondingsubpixel groups.

In FIG. 15, a single blue vertical line 1502 is displayed by fullyturning on the blue subpixels (i.e., the value of the blue subpixel is255) in the corresponding subpixel groups 1504, 1506. For example, ineach odd row of subpixels, the blue subpixels in the correspondingsubpixel groups 1504 are turned on; in each even row of subpixels, theblue subpixels in the corresponding subpixel groups 1506 are turned on.It is understood that because of the staggered arrangement betweenadjacent rows, the blue subpixels in adjacent rows are not strictlyaligned in the vertical direction and thus, the single blue verticalline 1502 in this example is not a straight line. However, the humanvision system would consider the single blue vertical line 1502 as astraight line when viewed from a distance.

In FIG. 16, two adjacent blue vertical lines 1602, 1604 are displayed byfully or partially turning on the blue subpixels in the correspondingsubpixel groups 1606, 1608, 1610. In each odd row, the blue subpixels inthe corresponding subpixel groups 1606 are partially turned on (i.e.,the value of the blue subpixel is larger than 0 and smaller than 255).In each even row of subpixels, the blue subpixels in the two adjacentsubpixel groups 1608, 1610 are fully turned on (i.e., the value of theblue subpixel is 255). Similarly, the human vision system would considerthe two adjacent blue vertical lines 1602, 1604 as two straight lineswhen viewed from a distance.

In FIG. 17, two separate blue vertical lines 1702, 1704 are displayed byfully turning on the blue subpixels (i.e., the value of the bluesubpixel is 255) in the corresponding subpixel groups 1706, 1708, 1710,1712. In each odd row of subpixels, the blue subpixels in the MOadjacent subpixel groups 1706, 1708 are turned on; in each even row ofsubpixels, the blue subpixels in the two adjacent subpixel groups 1710,1712 are turned on. Similarly the human vision system would consider thetwo separate blue vertical lines 1702, 1704 as two straight lines whenviewed from a distance.

FIG. 18 depicts a subpixel arrangement of an LED lamp display inaccordance with one embodiment set forth in the disclosure. FIG. 18 maybe for example, a plan view of the display 102 and depicts one exampleof the subpixel arrangements of the display 102. The display 102 in thisexample is an LED lamp display, such as a billboard display with anarray 1800 of LED lamps 1802. Each LED lamp 1802 may be considered as asubpixel group, which repeats itself horizontally in each row of thearray 1800. Similar to the arrangement of subpixel groups 302 in FIG. 3,LED lamps 1802 in each row of the array 1800 are staggered relative toLED lamps 1802 in an adjacent row of the array 1800 by, for example,half of the width of an LED lamp 1802. LED lamps 1802 in interval rowsare aligned along the vertical direction. Each LED lamp 1802 in thisembodiment is an assembly packaging of five LEDs which can beindividually controlled. Each LED lamp 1802 includes one LED in a firstcolor A, two LEDs in a second color B, and two LEDs in a third color C.A, B, and C in FIG. 18 denote three different colors, such as but notlimited to, red, green, blue, yellow, cyan, or magenta. In one examplethe first color A is blue, and the second and third colors B, C aregreen and red. When all the LEDs in an LED lamp 1802 are turned on theLED lamp 1802 emits the white light.

In this embodiment, the five LEDs A, B, B, C, and C are arranged in thesame pattern in each LED lamp 1802. For each LED lamp 1802, the two LEDsin the second color B, are on different sides of the LED in the firstcolor A along the horizontal direction, and the two LEDs in the thirdcolor C are on different sides of the LED in the first color A along thehorizontal direction as well. In other words, in each LED lamp 1802, oneLED B and one LED C are in the left part of the LEI) lamp 1802, theother LED 13 and the other LED C are in the right part of the LED lamp1802, and the LED A is in the middle of the LED lamp 1802.

In this embodiment, in each LED lamp 1802, one LED B is aligned with oneLED C along the vertical direction on the left side of the LED A, andthe other LED B is aligned with the other LED C along the verticaldirection on the right side of the LED A. Different from the exampleshown in FIG. 3, in this embodiment, one LED B is aligned with one LED Calong the horizontal direction, and the other LED B is aligned with theother LED C along, the horizontal direction. In other words, the twoLEDs in the same colors (i.e., B and B, or C and C) are arranged flushwith each other along the diagonal direction, and the two LEDs in thedifferent colors (i.e., B and C) are arranged flush with each othervertically or horizontally.

FIG. 19 illustrates one example of pixel division for the subpixelarrangement shown in FIG. 18. In this example, each LED lamp 1802 isdivided into two pixels 1902, 1904 such that, each of the two pixels1902, 1904 includes one of the two LEDs in the second color (e.g., G)and one of the two LEDs in the third color (e.g., R), and that the LEDin the first color (e.g., B) is shared by the two pixels 1902, 1904. Asshown in FIG. 19, the LED lamp 1802 is evenly divided through the middleof the blue LED into a left part corresponding to one pixel 1902, and aright part corresponding to another pixel 1904. The pixel 1902 includesone green LED, one red LED, and the left part of the blue LED the pixel1904 includes one red LED, one green LED, and the right part of the blueLED. That is, each blue LED on the display is shared by two adjacentpixels. It is understood that, in other examples, each LED lamp mayinclude one red LED, two green LEDs, and two blue LEDs, and the red LEDis in the middle of the LED lamp and shared by two adjacent pixels.

FIG. 20 depicts one example of a method for subpixel rendering on adisplay. The method may be implemented by the control logic 104 of theapparatus 100 or on any other suitable machine having at least oneprocessor. The control logic 104 may include logic and module(s) toperform each step of the method described below. The “logic” and“module” referred to herein are defined as any suitable software,hardware, firmware, or any suitable combination thereof that can performthe desired function, such as programmed processors, discrete logic, forexample, state machine, to name a few. The method for renderingsubpixels may be applied to any one of the subpixel arrangementsprovided above in FIGS. 3-19 or any other suitable subpixel arrangementin accordance with the present disclosure.

Beginning at 2002, a plurality pieces of display data for displaying aplurality of pixels are received. Each piece of display data includes afirst, a second, and a third components representing a first, a second,and a third colors, respectively. In this example, the first color isblue, and the second and third colors are green and red. As noted above,the display data 106 may be programmed at the pixel level and thus andinclude three components of data for rendering three subpixels withdifferent colors (e.g., three primary colors of red, green, and blue)for each pixel on the display 102. Referring now to FIG. 21, forexample, a first piece of display data 2102 for a first pixie 2104 maybe represented as (r1, g1, b1). Each of the three components r1, g1, b1may have a value from 0 to 255. When all the three components are set as255, the three subpixels in the first pixel 2104 are fully turned on,and the pixel presents the white color; when all the three componentsare set as 0, the three subpixels in the first pixel 2104 are fully turnoff, and the first pixel 2104 presents the black color. Similarly, asecond piece of display data 2106 of a second pixel 2108 that isadjacent to the first pixel 2104 in the same row may be represented as(r2, g2, b2). As noted above, the first and second pixels 2104, 2108 aredivided from the same subpixel group 2110 and share the blue subpixel Bin the subpixel group 2110. Each of the pixels 2104, 2108 furtherincludes a green subpixel G and a red subpixel R.

Referring hack to FIG. 20, at 2004, control signals 108 for renderingthe array of subpixel groups on the display 102 are provided based onthe plurality pieces of display data 106. In one embodiment, at 2006,for each subpixel in the first color, a respective control signal isprovided based on first components of two pieces of display data fordisplaying the two pixels that share the subpixel in the first color. Inone example, the respective control signal is obtained by calculatingthe weighted average of the first components of the two pieces ofdisplay data. Referring now to FIG. 21, the control signal 2112 fordriving the blue subpixel is obtained by calculating the weightedaverage of the blue components of the first and second pieces of displaydata 2102, 2106. For example, the calculation may be performed using thefollowing equations:b′=w1×b1+w2×b2  (1)where b′ is the value of the control signal 2112 for the blue subpixel,b1, b2 are the values of the blue components of the two pieces ofdisplay data 2102, 2106, respectively, and w1, w2 are weights of b1, b2,respectively. In one example, both w1 and w2 equal to ½, 4, and b′ isthe average of b1 and b2. It is understood that the values of w1, w2 maybe different in other examples. As to the green and red subpixels, thecorresponding components in the corresponding pixels may be useddirectly to provide the control signals for driving the green and redsubpixels. As shown in FIG. 21, g1 is used to provide the control signalfor the green subpixel in the first pixel 2104, and r1 is used toprovide the control signal for the red subpixel in the first pixel 2104.Similarly, g2 is used to provide the control signal for the greensubpixel in the second pixel 2108, and r2 is used to provide the controlsignal for the red subpixel in the second 2108. It is understood that,in other examples, the first color may be red, and the weighted averageof the red components of the first and second pieces of display may becalculated in the same manner as described above.

FIG. 22 depicts another example of subpixel arrangement of an OLEDdisplay in accordance with one embodiment set forth in the disclosure.FIG. 22 may be, for example, a plan view of the display 102 and depictsone example of the subpixel arrangements of the display 102. The display102 includes an array 2200 of subpixel groups 2202. Each subpixel group2202 in this embodiment includes six subpixels: two subpixels in a firstcolor A, two subpixels in a second color 13, and two subpixels in athird color C. A, B, and C in FIG. 22 denote three different colors,such as but not limited to, red, green, blue, yellow, cyan, magenta, orwhite. In one example, the first color A is blue, and the second andthird colors B, C are green and red. Subpixel groups 2202 in each row ofthe array 2200 are repeated along the horizontal direction. Subpixelgroups 2202 in each row of the array 2200 are staggered relative tosubpixels groups 2202 in an adjacent row of the array 2200. In otherwords, subpixel groups 2202 in adjacent rows are staggered along thehorizontal direction. In this embodiment, subpixel groups 2202 ininterval rows are aligned along the vertical direction. That is,subpixel groups 2202 in each odd row are aligned along the verticaldirection, and subpixel groups 2202 in each even row are aligned alongthe vertical direction. Stated in another way, subpixel groups 2202 ineach row are arranged repeatedly, and the subpixel groups 2202 inadjacent rows are arranged shifted from each other by, for example, ½ ofthe repeat pitch. In another example, the first color A is red, and thesecond and third colors B, C are green and blue.

In this embodiment, the six subpixels A, A, B, B, C, and C are arrangedin the same pattern in each subpixel group 2202. For each subpixel group2202, the two subpixels in the second color B are on different sides ofthe two subpixel in the first color A along the horizontal direction,and the two subpixels in the third color C are on different sides of thetwo subpixels in the first color A along the horizontal direction aswell. That is, in the horizontal direction, the two subpixels A arebetween the two subpixels B, and also between the two subpixels C. Inother words, in each subpixel group 2202, one subpixel B and onesubpixel C are in the left part of the subpixel group 2202, the othersubpixel B and the other subpixel C are in the right part of thesubpixel group 2202, and the two subpixels A are in the middle of thesubpixel group 2202. In each subpixel group 2202, the two subpixels Bhave the same size and shape, and the two subpixels C have the same sizeand shape as well.

In this embodiment, in each subpixel group 2202, one subpixel B isaligned with one subpixel C along the vertical direction on the leftside of the two subpixels A, and the other subpixel B is aligned withthe other subpixel C along the vertical direction on the right side ofthe two subpixels A. The two subpixels B are aligned with each otheralong the horizontal direction, and the two subpixels C are aligned witheach other along the horizontal direction as well. In other words, thetwo subpixels in the same colors (i.e., B and B, or C and C) arearranged flush with each other horizontally, and the two subpixels inthe different colors (i.e., B and C) are arranged flush with each othervertically. It is understood that even if two subpixels have differentsizes and/or shapes, they are considered as being “aligned” if thecenters of the two subpixels are aligned vertically or horizontally.

In this embodiment, each subpixel group 2202 is divided into two pixels2204, 2206 such that each of the two pixels 2204, 2206 includes one ofthe two subpixels in the first color A, one of the two subpixels in thesecond color B, and one of the two subpixels in the third color C. Asshown in FIG. 22, the subpixel group 2202 is evenly divided into a leftpart corresponding to one pixel 2204 and a right part corresponding toanother pixel 2206.

In this embodiment, each subpixel corresponds to an OILED, and for eachsubpixel group 2202, the two OLEDs in the first color (e.g., blue orred) have the same shape and size and share the same organiclight-emitting layer in the similar manner as discussed above withrespect to FIG. 5. Each of the OLEDs in this embodiment has asubstantially rectangular shape. However, it is understood that theshape of each subpixel in other examples may vary. Other shapes of thesubpixels include, but are not limited to, substantially round,triangle, square, pentagon, hexagon, heptagon, octagon, or any othersuitable shape. It is understood that the subpixels are not limited toOLEDs and may be, for example, LEDs of a billboard display with LEDlamps or any other suitable display devices as known in the art.

FIG. 23 depicts still another example of subpixel arrangement of an OLEDdisplay in accordance with one embodiment set forth in the disclosure.FIG. 23 may be, for example, a plan view of the display 102 and depictsone example of the subpixel arrangements of the display 102. The display102 includes an array 2300 of subpixel groups 2302. Each subpixel group2302 in this embodiment includes five subpixels: one subpixel in a firstcolor A, two subpixels in a second color B, and two subpixels in a thirdcolor C. A. B, and C in FIG. 23 denote three different colors, such asbut not limited to, red, green, blue, yellow, cyan, magenta, or white.In one example, the first color A is blue, and the second and thirdcolors B, C are green and red. Subpixel groups 2302 in each row of thearray 2300 are repeated along the horizontal direction. Subpixel groups2302 in each row of the array 2300 are staggered relative to subpixelsgroups 2302 in an adjacent row of the array 2300. In other words,subpixel groups 2302 in adjacent rows are staggered along the horizontaldirection. In this embodiment, subpixel groups 2302 in interval rows arealigned along the vertical direction. That is, subpixel groups 2302 ineach odd row are aligned along the vertical direction, and subpixelgroups 2302 in each even row are aligned along the vertical direction.Stated in another way, subpixel groups 2302 in each row are arrangedrepeatedly, and the subpixel groups 2302 in adjacent rows are arrangedshifted from each other by, for example, ½ of the repeat pitch. Inanother example, the first color A is red, and the second and thirdcolors B, C are green and blue.

In this embodiment, the five subpixels A, B, B, C, and C are arranged inthe same pattern in each subpixel group 2302. For each subpixel group2302, the two subpixels in the second color B are on the same side ofthe subpixel in the first color A along the vertical direction. In otherwords, the two subpixels B are above the subpixel A in each subpixelgroup 2302. The two subpixels in the third color C are on differentsides of the subpixel in the first color A along the horizontaldirection. That is, in the horizontal direction, the subpixel A isbetween the two subpixels C. In each subpixel group 2302, the twosubpixels B have the same size and shape, and the two subpixels C havethe same size and shape as well. However, in this embodiment, the sizeand shape of the subpixel B may be different from the size and shape ofthe subpixel C.

In this embodiment, in each subpixel group 2302, the two subpixels B arealigned with each other along the horizontal direction, and the twosubpixels C are aligned with each other along the horizontal directionas well. In other words, the two subpixels in the same colors (i.e., Band B, or C and C) are arranged flush with each other horizontally. Itis understood that even if two subpixels have different sizes and/orshapes, they are considered as being “aligned” if the centers of the twosubpixels are aligned vertically or horizontally.

In this embodiment, each subpixel group 2302 is divided into two pixels2304, 2306 such, that each of the two pixels 2304, 2306 includes one ofthe two subpixels in the second color B, one of the two subpixels in,the third color C, and shares the subpixel in the first color A. Asshown in FIG. 23, the subpixel group 2302 is evenly divided into a leftpart corresponding to one pixel 2304 and a right part corresponding toanother pixel 2306.

In this embodiment, each subpixel corresponds to an LED, and in eachsubpixel group 2302, the OLED in the third color C shares the sameorganic light-emitting layer with a respective OLED in the third color Cin the adjacent subpixel group 2302 in the same row of the array 2300.In this embodiment, in each subpixel group 2302, the two OLEDs in thesecond color B share the same organic light-emitting layer in thesimilar manner as discussed above with respect to FIG. 5. In eachsubpixel group 2302, the OLED in the second color B also shares the sameorganic light fitting layer with a respective OLED in the second color Bin the adjacent subpixel group 2302 in the same row of the array 2300.That is, in this embodiment, all OLEDs in the second color B in the samerow of the array 2300 share the same organic light-emitting layer 2308,which is fabricated through as “slit” opening on the evaporation mask.

Each of the OLEDs in this embodiment has a substantially rectangularshape. However, it s understood that the shape of each subpixel in otherexamples may vary. Other shapes of the subpixels include, but are notlimited to, substantially round, triangle, square, pentagon, hexagon,heptagon, octagon, or any other suitable shape. It is understood thatthe subpixels are not limited to OLEDs and may be, for example, LEDs ofa billboard display with LED lamps or any other suitable display devicesas known in the art.

Aspects of the method for subpixel rendering on a display, as outlinedabove, may be embodied in programming. Program aspects of the technologymay be thought of as “products” or “articles of manufacture” typicallyin the form of executable code and/or associated, data that is carriedon or embodied in a type of machine readable medium. Tangiblenon-transitory “storage” type media include any or all of the memory orother storage for the computers, processors or the like, or associatedmodules thereof, such as various semiconductor memories, tape drives,disk drives and the like, which may provide storage at any time for thesoftware programming.

All or portions of the software may at times be communicated through anetwork such as the Internet or various other telecommunicationnetworks. Such communications, for example, may enable loading of thesoftware from one computer or processor into another. Thus, another typeof media that may bear the software elements includes optical,electrical and electromagnetic waves, such as used across physicalinterfaces between local devices, through wired and optical landlinenetworks and over various air-links. The physical elements that carrysuch waves, such as wired or wireless links, optical links or the like,also may be considered as media bearing the software. As used herein,unless restricted to tangible “storage” media, terms such as computer ormachine “readable medium” refer to any medium that participates inproviding instructions to a processor for execution.

Hence, a machine readable medium may take many forms, including but notlimited to, a tangible storage medium, a carrier wave medium or physicaltransmission medium. Non-volatile storage media include, for example,optical or magnetic disks, such as any of the storage devices in anycomputer(s) or the like, which may be used to implement the system orany of its components as shown in the drawings. Volatile storage mediainclude dynamic memory, such as a main memory of such a computerplatform. Tangible transmission media include coaxial cables; copperwire and fiber optics, including the wires that form a bus within acomputer system. Carrier-wave transmission media can take the form ofelectric or electromagnetic signals, or acoustic or light waves such asthose generated during radio frequency (RF) and infrared (IR) datacommunications. Common forms of computer-readable media thereforeinclude for example: a floppy disk, a flexible disk, hard disk, magnetictape, any other magnetic medium, a CD-ROM, DVD or DVD-ROM, any otheroptical medium, punch cards paper tape, any other physical storagemedium with patterns of holes, a RAM, a PROM and EPROM, a FLASH-EPROM,any other memory chip or cartridge, a carrier wave transporting data orinstructions, cables or links transporting such a carrier wave, or anyother medium from which a computer can read programming code and/ordata. Many of these forms of computer readable media may be involved incarrying one or more sequences of one or more instructions to aprocessor for execution.

The above detailed description of the disclosure and the examplesdescribed therein have been presented for the purposes of illustrationand description only and not by limitation. It is therefore contemplatedthat the present disclosure cover any and all modifications, variationsor equivalents that fall within the spirit and scope of the basicunderlying principles disclosed above and claimed herein.

What is claimed is:
 1. An apparatus comprising: a display panelcomprising an array of subpixel groups arranged in columns and rows,wherein: each of the subpixel groups consists of one subpixel of a firstcolor, two subpixels of a second color, and two subpixels of a thirdcolor, in each of the subpixel groups, a center of at least one of thetwo subpixels of the second color has an offset from a center of thesubpixel of the first color along a column direction, and a center of atleast one of the two subpixels of the third color has another offsetfrom the center of the subpixel of the first color along an oppositedirection of the column direction, subpixel groups in each row of thearray are repeated along the row direction, subpixel groups in each rowof the array are staggered relative to subpixels groups in an adjacentrow of the array along the column direction, and for each of thesubpixel groups, each of the subpixels of three colors is staggered witheach of the subpixels of a same color in a subpixel group in an adjacentrow along the column direction, and each of the subpixels of the threecolors is aligned with one of the subpixels of the same color in asubpixel group in an alternating row along the column direction.
 2. Theapparatus of claim 1, wherein in each of the subpixel groups, a size ofa subpixel of the first color is larger than a size of a subpixel of thesecond color and a size of a subpixel of the third color.
 3. Theapparatus of claim 1, wherein in each of the subpixel groups, the twosubpixels of the second color are on different sides of the subpixel ofthe first color along a row direction; and the two subpixels of thethird color are on different sides of the subpixel of the first coloralong the row direction.
 4. The apparatus of claim 3, wherein each ofthe subpixel groups is divided into two pixels such that each of the twopixels includes one of the two subpixels of the second color and one ofthe two subpixels of the third color, and that the subpixel in the firstcolor is shared by the two pixels.
 5. The apparatus of claim 4, furthercomprising: control logic operatively coupled to the display panel andconfigured to receive display data and convert the display data intocontrol signals for driving the array of subpixel groups, wherein thecontrol logic is further configured to, for each subpixel of the firstcolor, provide a respective control signal based on two pieces ofdisplay data for displaying the two pixels that share the subpixel inthe first color.
 6. The apparatus of claim 1, wherein in each of thesubpixel groups, the two subpixels of the second color are aligned alonga row direction; and the two subpixels of the third color are alignedalong the row direction.
 7. The apparatus of claim 1, wherein in each ofthe subpixel groups, the two subpixels of the second color have sameshapes and sizes; and the two subpixels of the third color have sameshapes and sizes.
 8. The apparatus of claim 1, wherein in each of thesubpixel groups, each of the subpixels has a substantially rectangularshape.
 9. The apparatus of claim 1, wherein in each of the subpixelgroups, the first color is blue or red.
 10. The apparatus of claim 1,wherein the subpixel groups in each row of the array are staggeredrelative to the subpixels groups in the adjacent row of the array byhalf of a width of a subpixel group.
 11. The apparatus of claim 1,wherein in each of the subpixel groups, the two subpixels of the secondcolor are on a same side of the subpixel of the first color along thecolumn direction; and the two subpixels of the third color are ondifferent sides of the subpixel of the first color along a rowdirection.
 12. An apparatus comprising: a display comprising: a displaypanel having a light-emitting substrate comprising an array of subpixelgroups arranged in columns and rows, a subpixel in each of the subpixelgroups corresponding to an organic light-emitting diode (OLED), and adriving substrate comprising an array of driving elements, each drivingelement configured to drive a respective OLED; and control logicoperatively coupled to the display and configured to receive displaydata and convert the display data into control signals for driving thearray of subpixel groups, wherein: each of the subpixel groups consistsof one OLED of a first color, two OLEDs of a second color, and two OLEDsof a third color, the OLED of the first color positioned between the twoOLEDs of the second color and between the two OLEDs of the third color,in each of the subpixel groups, centers of the two OLEDs of the secondcolor are aligned along a row direction, centers of the two OLEDs of thethird color are aligned along the row direction, and centers of an OLEDof the second color and an OLED of the third color are aligned along acolumn direction, subpixel groups in each row of the array of subpixelgroups are repeated along the row direction, subpixel groups in each rowof the array of subpixel groups are staggered relative to subpixelsgroups in an adjacent row of the array of subpixel groups along thecolumn direction, and for each of the subpixel groups, each of the OLEDsof three colors is staggered with each of the OLEDs of a same color in asubpixel group in an adjacent row along the column direction, and eachof the OLEDs of the three colors is aligned with one of the OLEDs of thesame color in a subpixel group in an alternating row along the columndirection.
 13. The apparatus of claim 12, wherein in each of thesubpixel groups, a size of an OLED of the first color is larger than asize of an OLED of the second color and an OLED of the third color. 14.The apparatus of claim 12, wherein each of the subpixel groups isdivided into two pixels such that, each of the two pixels includes oneof the two OLEDs of the second color and one of the two OLEDs of thethird color, and that the OLED of the first color is shared by the twopixels.
 15. The apparatus of claim 14, wherein the control logic isfurther configured to, for each OLED of the first color, provide arespective control signal based on two pieces of display data fordisplaying the two pixels that share the OLED of the first color. 16.The apparatus of claim 12, wherein in each of the subpixel groups, eachof the two OLEDs of the second color is aligned with a respective one ofthe two OLEDs of the third color along the column direction.
 17. Theapparatus of claim 12, wherein in each of the subpixel groups, the twoOLEDs of the second color are aligned along the row direction; and thetwo OLEDs of the third color are aligned along the row direction. 18.The apparatus of claim 12, wherein in each of the subpixel groups, thetwo OLEDs of the second color have same shapes and sizes; and the twoOLEDs of the third color have same shapes and sizes.
 19. The apparatusof claim 12, wherein in each of the subpixel groups, each of the OLEDshas a substantially rectangular shape.
 20. The apparatus of claim 12,wherein in each of the subpixel groups, the first color is blue or red.21. The apparatus of claim 12, wherein the subpixel groups in each rowof the array are staggered relative to the subpixels groups in theadjacent row of the array by half of a width of a subpixel group. 22.The apparatus of claim 12, wherein in each of the subpixel groups, thetwo OLEDs of the second color are on a same side of the OLED of thefirst color along the column direction; and the two OLEDs of the thirdcolor are on different sides of the OLED of the first color along therow direction.
 23. The apparatus of claim 12, wherein all OLEDs of thesecond color in the same row of the array share the same organiclight-emitting layer.
 24. An apparatus comprising: a display comprisingan array of light-emitting diode (LED) lamps arranged in columns androws; and control logic operatively coupled to the display andconfigured to receive display data and convert the display data intocontrol signals for driving the array of LED lamps, wherein: each of theLED lamps consists of one LED of a first color, two LED of a secondcolor, and two LEDs of a third color, in each of the LED lamps, a centerof at least one of the two LEDs of the second color has an offset from acenter of the LED of the first color along a column direction, and acenter of at least one of the two LEDs of the third color has anotheroffset from the center of the LED of the first color along an oppositedirection of the column direction, for each of the LED lamps, each ofthe LEDs of three colors is staggered with each of the LEDs of a samecolor of an LED lamp in an adjacent row along the column direction, andeach of the LEDs of the three colors is aligned with one of LEDs of thesame color in an LED lamp in an alternating row along the columndirection, LED lamps in each row of the array are repeated along the rowdirection, LED lamps in each row of the array are staggered relative toLED lamps in an adjacent row of the array along the column direction,and for each of the LED lamps, each of the LEDs of three colors isstaggered with each of the LEDs of a same color in a subpixel group inan adjacent row along the column direction, and each of the LEDs of thethree colors is aligned with one of the LEDs of the same color in an LEDlamp in an alternating row along the column direction.
 25. The apparatusof claim 24, wherein each of the LED lamps emits a white light when allLEDs in the LED lamp are turned on.
 26. The apparatus of claim 24,wherein in each of the LED lamps, the two LEDs of the second color areon different sides of the LED of the first color along a row direction;and the two LEDs of the third color are on different sides of the LED ofthe first color along the row direction.
 27. The apparatus of claim 26,wherein each of the LED lamps is divided into two pixels such that eachof the two pixels includes one of the two LEDs of the second color andone of the two LEDs of the third color, and that the LED of the firstcolor is shared by the two pixels.
 28. The apparatus of claim 27,wherein the control logic is further configured to, for each LED of thefirst color, provide a respective control signal based on two pieces ofdisplay data for displaying the two pixels that share the LED of thefirst color.
 29. The apparatus of claim 24, wherein in each of the LEDlamps, the first color is blue or red.
 30. The apparatus of claim 24,wherein the LED lamps in each row of the array are staggered relative tothe LED lamps in the adjacent row of the array by half of a width of anLED lamp.
 31. A method, implemented on a machine having at least oneprocessor, for subpixel rendering on a display, comprising: receiving aplurality pieces of display data for displaying a plurality of pixels,each piece of display data comprising a first, a second, and a thirdcomponents representing a first, a second, and a third colors,respectively; and providing control signals for rendering an array ofsubpixel groups arranged in columns and rows on the display based on theplurality pieces of display data, wherein: each of the subpixel groupsforms a first pixel and a second pixel and consists of one subpixel ofthe first color, two subpixels of the second color, and two subpixels ofthe third color, the first pixel and the second pixel sharing thesubpixel of the first color, in each of the subpixel groups, a center ofat least one of the two subpixels of the second color has an offset froma center of the subpixel of the first color along a column direction,and a center of at least one of the two subpixels of the third color hasanother offset from the center of the subpixel of the first color alongan opposite direction of the column direction, subpixel groups in eachrow of the array are repeated along the row direction, subpixel groupsin each row of the array are staggered relative to subpixels groups inan adjacent row of the array along the column direction, each of thefirst pixel and the second pixel includes one of the two subpixels ofthe second color and one of the two subpixels of the third color, andfor each of the subpixel groups, each of the subpixels of three colorsis staggered with each of the subpixels of a same color in a subpixelgroup in an adjacent row along the column direction, and each of thesubpixels of the three colors is aligned with one of the subpixels ofthe same color in a subpixel group in an alternating row along thecolumn direction.
 32. The method of claim 31, wherein: providing controlsignals comprises, for each subpixel of the first color, providing arespective control signal based on a first color component correspondingto a first piece of display data and a second color componentcorresponding to a second piece of display data for displaying the firstpixel and the second pixel.
 33. The method of claim 32, wherein a weightfor each of the first color component and the second color component ofdisplay data equals ½.
 34. A non-transitory machine-readable mediumhaving information recorded thereon for subpixel rendering on a display,wherein the information, when read by a machine, causes the machine toperform the following: receiving a plurality pieces of display data fordisplaying a plurality of pixels, each piece of display data comprisinga first, a second, and a third components representing a first, asecond, and a third colors, respectively; and providing control signalsfor rendering an array of subpixel groups arranged in columns and rowson the display based on the plurality pieces of display data, wherein:each of the subpixel group consists of one subpixel of the first color,two subpixels of the second color, and two subpixels of the third color,in each of the subpixel groups, a center of at least one of the twosubpixels of the second color has an offset from a center of thesubpixel of the first color along a column direction, and a center of atleast one of the two subpixels of the third color has another offsetfrom the center of the subpixel of the first color along an oppositedirection of the column direction, subpixel groups in each row of thearray are repeated along the row direction, subpixel groups in each rowof the array are staggered relative to subpixels groups in an adjacentrow of the array along the column direction, for each of the subpixelgroups, each of the subpixels of three colors is staggered with each ofthe subpixels of a same color in a subpixel group in an adjacent rowalong the column direction, and each of the subpixels of the threecolors is aligned with one of the subpixels of the same color in asubpixel group in an alternating row along the column direction, andeach of the subpixel group is divided into two pixels such that each ofthe two pixels include one of the two subpixels of the second color andone of the two subpixels of the third color, and that the subpixel ofthe first color is shared by the two pixels.
 35. The medium of claim 34,wherein providing control signals comprises, for each subpixel of thefirst color, providing a respective control signal based on colorcomponents of two pieces of display data for displaying the two pixelsthat share the subpixel of the first color.
 36. The medium of claim 35,wherein providing a respective control signal comprises calculating aweighted average of the color components of the two pieces of displaydata.
 37. The medium of claim 36, wherein a weight for each of the colorcomponents of the two pieces of display data equals ½.
 38. The apparatusof claim 7, wherein in each of the subpixel groups, the subpixels of thesecond and third colors have same shapes and sizes.
 39. The apparatus ofclaim 12, wherein in each of the subpixel groups, each of the two OLEDsof the second color shares a same organic light-emitting layer with anOLED of the second color in an adjacent subpixel group in the same rowof the array of subpixel groups, and each of the two OLEDs of the thirdcolor shares a same organic light-emitting layer with an OLED of thethird color in an adjacent subpixel group in the same row of the arrayof subpixel groups.